i) Field of the Invention
The present invention relates to an information storage apparatus in which an information storage medium is used.
ii) Description of Related Art
Information storage apparatuses such as a hard disk drive and a magnetooptic (MO) disk drive have heretofore been known, and in the information storage apparatus, a disk-like information storage medium is used. The information storage apparatus is incorporated into a computer system as the information storage apparatus for a computer in many cases.
In recent years, information communication networks such as Internet have rapidly been developed, and with the development, portable computer systems such as a notebook-isize personal computer have also been developed. When the aforementioned information storage apparatus is incorporated and utilized in the portable computer system, it is necessary to operate the information storage apparatus by a battery or a galvanic cell. Moreover, in order to lengthen life of the battery or the galvanic cell, and construct the portable computer system which can be utilized for a long time, development of the information storage apparatus with a little current consumption has strongly been demanded.
Additionally, in the information storage apparatus, the information storage medium is rotated at a high speed by a spindle motor or the like to access the information storage medium, and the current consumption in the spindle motor occupies a large proportion of the current consumption of the information storage apparatus. Therefore, it is an important problem to reduce the current consumption in the spindle-motor or the like.
This problem is a particularly remarkable problem when the apparatus is incorporated into the portable computer system, but also occurs when the apparatus is incorporated in a desktop computer system, or when the apparatus has its own power source.
The present invention has been developed in consideration of the aforementioned circumstances, and an object thereof is to provide an information storage apparatus in which current consumption in a spindle motor or the like is low. By realizing such information storage apparatus, it is possible to construct a portable computer system whose long-time use is possible with a battery or a galvanic cell.
To achieve the aforementioned object, according to the present invention there is provided an information storage apparatus for holding an information storage medium in a predetermined position and rotating the information storage medium in a predetermined direction to perform at least information reproduction with respect to the information storage medium.
The information storage apparatus comprises: a driver for driving the information storage medium in the predetermined direction; a brake for forcibly stopping rotating the information storage medium; and a controller for selectively executing a forced stop operation in which the driver stops driving the information storage medium and the brake forcibly stops rotating the information storage medium, and a natural stop operation in which the driver only stops driving the information storage medium.
Here, the xe2x80x9cinformation storage mediumxe2x80x9d includes an optical disk, a flexible disk and a hard disk, and further includes non-disk-like information storage media such as a card-like information storage medium. Moreover, the xe2x80x9cinformation storage mediumxe2x80x9d may be either a transportable medium or a built-in medium.
The forced stop operation consumes more current than the natural stop operation because the operation of the brake is necessary. Therefore, by appropriately and selectively executing the forced stop operation and the natural stop operation by the information storage apparatus of the present invention to avoid a wasteful forced stop operation, current consumption can be depressed.
For the information storage apparatus of the present invention, with the transportable information storage medium, it is preferable that xe2x80x9cthe information storage apparatus further comprises: an ejector for ejecting the information storage medium out of the predetermined position; and a judgment section for judging whether a state of the information storage medium is a rotating state or a stop state, and the controller not only selectively (uses and) executes the forced stop operation and the natural stop operation but also allows the ejector to execute an eject operation for ejecting the information storage medium, and in order to execute the eject operation, the controller executes the forced stop operation to stop the information storage medium and subsequently executes the eject operation in a case in which the judgment section judges that the state is the rotating state, and executes the eject operation as it is in a case in which the judgment section judges that the state is the stop statexe2x80x9d.
Here, the judgment section may judge that the state is the stop state when a time elapsed from a time to execute the forced stop operation and the natural stop operation is longer than a predetermined time, or may judge that the state is the stop state when a result of measurement of a rotational speed of the information storage medium or the driver is a predetermined rotational speed or less.
According to the information storage apparatus of the aforementioned preferable constitution, when the information storage medium is in the rotating state, the forced stop operation is executed, the information storage medium is prevented from being damaged during ejecting of the information storage medium, and a standby time is conveniently short until the ejecting of the information storage medium. Moreover, when the information storage medium is in the stop state, a wasteful forced stop operation is avoided and the current consumption is small.
Moreover, in the information storage apparatus of the present invention, the controller receives a predetermined starting signal and allows the driver to start driving the information storage medium, and in a case in which the controller allows the natural stop operation to be executed and subsequently receives the starting signal before the information storage medium stops, the information storage medium fails to stop and the controller preferably allows the driver to start driving the information storage medium.
When the controller allows the natural stop operation to be executed, for a certain degree of time, the information storage medium continues rotating by inertia.
According to the information storage apparatus of the aforementioned preferable constitution, when the information storage medium continues rotating and the starting signal is received, the current consumption can be depressed by utilizing a rotation energy.
Furthermore, in the information storage apparatus of the aforementioned preferable constitution, when the information storage medium fails to stop and the controller allows the driver to start driving the information storage medium, the controller performs a control on the driver in accordance with the rotational speed of the information storage medium.
According to the information storage apparatus of the preferable constitution, by performing the control on the driver in accordance with the rotational speed, the rotation energy of the information storage medium is efficiently utilized.